My responses to the questions in the FFA's ANPRM on transponder operation in gliders. Some of these are self explanatory but for others you will need to see the specific question in the federal register on the URL below. You are welcome to verify and use these

Responses below to ANPRM questions as in the Federal Register
http://www.gpo.gov/fdsys/pkg/FR-2015...2015-14818.htm


A TSO-C199 TABS

A1 TABS could be used in certain circumstances if the specification is appropriate i.e. cost, power requirements, physical size. These are not known at this stage and no TABS product can be purchased today
A2 No one solution fits all the needs to reasonably protect any and all users of the airspace.
Sectional charts could be better used to highlight areas of intensive glider operations. Local ATC and glider operations should work to define the needs in areas shared by other types of aircraft. eg as defined today for B and C airspaces.
The needs in these areas are very different from gliders operating in lightly used air space such as cruising on mountain ranges that are generally in remote areas where any airline traffic is far above in class A airspace.
Gliders by definition have limited power resources and need the flexibilty to use transponders in high activity areas but not in more remote places where the risks are much lower.
I suggest TABS or transponders are required in high traffic areas that are defined locally but are subject to pilot discretion otherwise. Glider pilots have no more desire to be involved in a mid air collision than does any one else.
Consider a well travelled glider route. An out and return from Minden NV south of Reno Class C south to the White Mountains past Bishop CA then the return. In the Minden airport area glider traffic patterns are to the east and power to the west and it is the local practice to make frequent radio calls on CTAF giving position reports and intention. This is completely successful in keeping the sky safe. Above 10,000 feet most gliders use transponders over the Carson Valley and the Pinenut mountains to the east and Sierras to the west. Normal approach should route aircraft as far from these areas as possible considering the limitations of ATC resources and TCAS type devices carried by many aircraft and all in the transport category.
Some older glider models are too low cost to justify the significant cost of transponder and/or TABS devices and need areas where they can operate with the current glider exemption.
South of the Pinenuts there is little traffic and no point in wasting power squawking into the blind, power that will be needed later. On the White Mountains there can be intensive high speed (120 knots so closing at 200 knots and more) glider traffic going north and south all seeking the same high energy lines. TABS is of zero protection here nor the "see and avoid" concept with sleek low profile machines that are essentially invisible to the human eye till it is too late to take evasive action. Here we need the non TSO PF, the European version of which has saved many lives.
Flights can last 10 hours and more and returning to the Carson Valley some hours later we need to have operating transponders. Also sufficient power is needed for self launch gliders for engine extension and start up that may be required at any stage of flight.
A3 No glider manufacturer offers a TABS device in a new machine as no product is available today. I have a Becker transponder that was installed in my glider in 2005 by the manufacturer, DG Sailplanes, for 2268 Euros and solar panels on the engine bay doors were 1033 Euros. The solar panels are not able to maintain voltage with the transponder and radio operating.
FAA representatives at OSH said TRiG would be the supplier of TABS. TRiG told me their low power TT21 transponder lists for $2800, the necessary TN70 GPS WAAS box for US 800$ to 1000, additional solar panels will cost $1900 with an estimated $500 plus for instillation. So an estimate of US$6300 on top of the money invested initially of 2400 Euros for a Becker Mode-C that is now just a paper weight.
A.3.1 Estimate ~$6300 as in A2
A3.2 USD 500+
A3.3 Unknown
A4 No plans as no TABS solution is available today. Cannot answer till we know cost, power budget, physical size and issues such as if class 2 is useable above 15,000 feet

B Transponder equipment and use in gliders

B1 No, but it should be modified. Low power, low cost, small size TABS devices need to be available for new instillations. Existing Mode C transponders cannot be used so the voluntary investment already made in safety is just thrown away.
Transponder/TABS use should be required in high density traffic areas defined locally by ATC and user groups. These areas should provide necessary protection for air space users but allow use with the exemption by gliders such as those used for basic training and with low hull value where the high cost of TABS cannot be economically justified. Transponder/TABS use in all other parts of the national air space should remain at the discretion of the PIC.
B2 Gliders will return after long flights with exhausted batteries and not be able to squawk in high risk areas and self launch gliders will not be able to deploy and start engines. Other avionics such as radios will not be able to transmit and and GPS devices will be unable to provide guidance. Short answer - safety will be compromised with perhaps disastrous results simply from using power in low risk areas
B3 See A3. Same questions
B4 If I have to junk my Becker Mode C transponder I guess I might as well go ADS-B despite the cost. So that is a very reluctant yes.

C ADS-B out in gliders

C1 Not all gliders should be required to incur the cost, power and size issues of installing ADS-B and equipment and use should be based on the air space and usage. One piece of airspace is not the same as another.
Gliders operating below 10,000 feet engaged in operations such as basic training near the airport of operation should not be burdened with this unnecessary and significant cost.
Local ATC and glider operations should work out the areas where ADS-B out is required based on local operations and use in other areas should remain excluded.
C2 There has only been one mid air incident in the last 9 years between a glider and an airplane. If ATC had not been vectoring high speed traffic through a known area of high intensity glider activity this incident would not have occurred. Local ATC and glider operations should negotiate sensible operating rules.
Glider to glider mid airs and near misses are a much more significant factor. The risk to airplanes from the rapidly growing and uncontrolled drone fleet is far higher as is currently being reported by airline crews.
C3 See A3 same questions
C4 I don't understand the question as the only TABS solution on the horizon is I believe from TRiG and that includes their TT21 mode S transponder. If by the question you mean a Mode C transponder must be retained or added in case ADS-B does nor work the answer is absolutely no. Ignoring cost I have no power or space in my glider to carry both systems. Not an option
C5 I have no plans today to add ADS-B to my glider as I do not understand the cost, power, space requirements and no product exists. Further my Becker 4401 meets the current requirements and changing today will prevent me taking advantage of future developments that likely will be cheaper and lower power.

D Additional considerations

D1 There has been only one mid air in the last 9 years between an airplane and a glider in the US air space but many more airplane to airplane and glider to glider, so glider to airplane would not seem to be a high risk justifying removing the glider exemption to transponder operation considering the cost, power, space and operating issues gliders uniquely have. Drone to aircraft is rapidly emerging as a much higher risk than glider to airplane.
To make glider operations safer without unnecessarily burdening the glider community the air space should be analyzed and solutions for each type proposed. e.g.
i High activity areas with mixed types of aircraft where transponders/TABS devices are required such as near class B, C and on approach and departure paths of IFR traffic at those major airports. Note that gliders do not normally operate in IFR conditions or flight plans. Air space should be segmented laterally and vertically and rules for use established between local ATC and glider operations. The Minden incident in 2006 might have been avoided if the glider had an operating transponder and would not have occurred if the jet had not been vectored through an known area of intense glider traffic. Time is a factor too as for instance gliders rarely operate at night. Weather conditions play are part as well as to when and where gliders can operate.
ii Areas of intense glider activity such as the ridges of the east coast Appalachian mountains and in the west mountain ranges such as the Sierras, Whites and Wasatch should be marked on charts as are MOAs. Glider traffic generally moves north south along these geographic features and power traffic east west minimizing risk. Gliders are unlikely to be operating at the selected altitudes as airplanes do following the VFR and IFR rules.
iii The risk between gliders operating in competitions and on long distance routes can be minimized with FLARM technology. FLARM has prevented many glider to glider incidents in Europe and PF is needed in the US for high risk glider to glider operations. Voluntary installation with some level of oversight by the Sailplane and Soaring Association especially for sanctioned contests and meets will be a satisfactory management system. Some soaring event are already mandating PF use.
It should be noted that gliders with PF can see transponder transmissions from other aircraft and take necessary avoidance action although PF cannot be seen by TCAS type devices nor ATC. But PF gives gliders the capability to "see and avoid" aircraft using transponders and at that point the transponder/TABS could then be activated.
D2 I have not had a collision or near miss in any aircraft
D3 I have had potential near misses in glider to glider situations avoided by the common practice of position reports in the blind on 123.3 but this is not a robust procedure
D4 No. I operate within 30 miles of but outside of and above some of the airspaces mentioned
Yes. I routinely operate above 10,000 MSL
D5 I rarely use ATC services flying my glider but I monitor the appropriate frequencies as necessary.